It's worth mentioning that if the GIFsicle command doesn't seem to have any impact, you should double-check that the background color is accurate. For example, in the preceding animation, the real backdrop color was #fdfffc (a very little yellow-greenish white) rather than #ffffff (pure white). You can't see the difference by sight (or, at least, I can't on this screen), but it's enough to make GIFsicle think the two colors are distinct. Also, since GIF files only allow 1-bit transparency, the borders of transparent portions will not be anti-aliased. This is OK as long as the backdrop you're presenting the animation on isn't too different from the original background color; if it is, you may see some unattractive color fringing around the borders of the animation. Unfortunately, there isn't much you can do about that other than change the backdrop or re-render the animation.
